Cmdr. Jeff Satur said the 17-year-old was stabbed twice. His injuries were serious, but not life-threatening.

"We initially thought a lung had been pierced, but that turned out not to be the case," Satur said.

Police have not released either boy's name. Both boys previously attended Faith Baptist School and are now students at Silver Creek High School, according to Times-Call reports and public information.

The stabbing was reported at about 7:20 p.m. as Sunday evening communion services were finishing. It occurred on the east side of the church, near the office doors.

Longmont police investigate a stabbing at Faith Baptist Church on Sunday night. A 15-year-old boy is suspected of stabbing his 17-year-old brother during an argument. (Paul Aiken / For the Times-Call)

Some church members helped stem the bleeding until the boy could be taken to Longmont United Hospital. Jackets that had been used to put pressure on the wounds remained on the pavement as officers investigated.

Congregants poured into the parking lot after the incident, with several praying or talking quietly; the victim's mother left shortly after the ambulance did.

Church member Norlin Cavender was among those who hurried outside after hearing the commotion.

"He was on the ground there, you could tell he'd been stabbed," said Cavender. "He was in a lot of pain, his mother was there. They were putting compresses on the wound, it looked like the lower back."

Dispatchers initially reported that the boy had been stabbed in the arm and the back.

The suspect was described as 5-feet, 10-inches tall, about 120 pounds, wearing a gray shirt and khaki pants. He still had the knife when he left the scene, Satur said. The suspect is not believed to be a danger to the general public, he said.

Cavender said the family were longtime members of the church who had moved away; they had returned to the area and to Faith Baptist about a year ago, he said.

Police were still searching for the younger brother as of 10 p.m. Sunday.

After 6 p.m. services at Faith Baptist Church, an argument between teenage brothers turned violent when a 15-year-old boy stabbed his 17-year-old brother in the back, police said. (Paul Aiken / For the Times-Call)

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